Available theories and prediction formulas on scour at bridge waterways are reviewed. Formulas that offer potential for prediction of scour around bridge piers are compared by reducing each formula to a non-dimensional form that includes Froude Number, the ratio of scour depth to pier width, and the ratio of stage to pier width. A field study to gather data on scour and related variables is described. The study is aimed at collecting field data in order to furnish a basis on which to compare scour prediction formulas.